# Array: Oject reference not set **URL:** \ **Category:** PowerShell Help\ **Created:** [September 24, 2024, 9:06pm UTC](https://forums.powershell.org/t/array-oject-reference-not-set/24795 "2024-09-24T21:06:08Z")\ **Posts on this page:** 3\ **Page:** 1
**Author:** ![PowershellUserName](https://avatars.discourse-cdn.com/v4/letter/p/838e76/32.png) [@PowershellUserName](https://forums.powershell.org/u/PowershellUserName)\ **Post date:** [September 24, 2024, 9:06pm UTC](https://forums.powershell.org/t/array-oject-reference-not-set/24795/1 "2024-09-24T21:06:08Z")
I am a newbie to PowerShell. I am working with Windows 10/11. I have been looking for a way to remove hidden serial ports. These can be seen in Device Manager if “Show Hidden” is enabled. I found this script online “removeGhosts.ps1”. It can be found at: > This script will list and delete the “hidden” devices. However, I want to be more selective with the delete, deleting only USB-RS232 dongles. When I run the script, the results are put into a PS array. However, I cannot access the array with an index. I get the error: “out-lineoutput : Object reference not set to an instance of an object”. I watched several YouTube videos. They give examples by populating the array with strings and then accessing the strings with an index, aka: MyArray[1]. That seems to be a simpler case than what I have. I read some forum entries that talk about this error but either it didn’t work in my situation or I did not understand it, probably the latter. 😉 Using PowerShell ISE, here are some commands from my PowerShell session. ############################## $Devices = .\removeGhosts.ps1 -listGhostDevicesOnly -narrowByClass Ports NarrowByClass: Ports List ghost devices without removal: True Total ghost devices found : 114 Total filtered ghost devices found : 12 ############################## $Devices.GetType() IsPublic IsSerial Name BaseType -------- -------- ---- -------- True True Object System.Array ############################## $Devices.Count 16 ############################## $Devices.Length 16 ############################## $Devices.IsFixedSize True ############################## $Devices FriendlyName HWID InstallState Class * * * Prolific USB-to-Serial Comm Port (COM6) USB\VID\_067B&PID\_2303&REV\_0400 False Ports Silicon Labs CP210x USB to UART Bridge (COM23) USB\VID\_10C4&PID\_EA60&REV\_0100 False Ports USB Serial Port (COM11) FTDIBUS\COMPORT&VID\_0403&PID\_6015 False Ports USB Serial Port (COM12) FTDIBUS\COMPORT&VID\_0403&PID\_6015 False Ports USB Serial Port (COM20) FTDIBUS\COMPORT&VID\_0403&PID\_6015 False Ports USB Serial Port (COM21) FTDIBUS\COMPORT&VID\_0403&PID\_6015 False Ports USB Serial Port (COM22) FTDIBUS\COMPORT&VID\_0403&PID\_6015 False Ports USB Serial Port (COM4) FTDIBUS\COMPORT&VID\_0403&PID\_6015 False Ports XDS110 Class Application/User UART (COM10) USB\VID\_0451&PID\_BEF3&REV\_0100&MI\_00 False Ports XDS110 Class Application/User UART (COM13) USB\VID\_0451&PID\_BEF3&REV\_0100&MI\_00 False Ports XDS110 Class Auxiliary Data Port (COM14) USB\VID\_0451&PID\_BEF3&REV\_0100&MI\_03 False Ports XDS110 Class Auxiliary Data Port (COM9) USB\VID\_0451&PID\_BEF3&REV\_0100&MI\_03 False Ports ############################## $Devices[1] out-lineoutput : Object reference not set to an instance of an object. + CategoryInfo : NotSpecified: (🙂 [out-lineoutput], NullReferenceException + FullyQualifiedErrorId : System.NullReferenceException,Microsoft.PowerShell.Commands.OutLineOutputCommand ############################## So, what I am hoping to do is iterate through the list to remove the “hidden” USB-to-RS232 serial ports. I do not want to remove the XDS110 units or any other device that might not be a USB/232 DB9 dongle. I guess I will have to search for: (“USB Serial Port”|Prolific|CP210x). Of course, I will have to expand that list as others become known. I think the first step is to be able to index through the array but I cannot figure it out. Any help will be appreciated. ---
**Author:** ![krzydoug](https://sea1.discourse-cdn.com/flex019/user_avatar/forums.powershell.org/krzydoug/32/1008_2.png) [@krzydoug](https://forums.powershell.org/u/krzydoug)\ **Post date:** [September 25, 2024, 8:01am UTC](https://forums.powershell.org/t/array-oject-reference-not-set/24795/2 "2024-09-25T08:01:53Z")
The issue is the author ruined the output by including formatting commands in the function. This is easily discovered by simply inspecting the output with `Get-Member` ![image](https://us1.discourse-cdn.com/flex019/uploads/powershell/original/2X/2/2e052ad95f45d2f00a78953b12ef18bda79525e6.png) I’ve corrected the script by removing the calls to Format-Table (alias ft) and you can find it here > ---
**Author:** ![system](https://us1.discourse-cdn.com/flex019/uploads/powershell/original/1X/385e4f9fe133561ad30a814262fe0e0ae6bc3ef0.png) [@system](https://forums.powershell.org/u/system)\ **Post date:** [October 25, 2024, 8:02am UTC](https://forums.powershell.org/t/array-oject-reference-not-set/24795/3 "2024-10-25T08:02:43Z")
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